The start codon is $$\text{AUG}$$ and codes for methionine.

Question 1

Which of the following best describes the central dogma of molecular biology?

Accepted Answer

DNA is transcribed into mRNA, which is then translated into protein.

Question 2

A mutation changes a codon from $$	ext{GAG} to$$ $$	ext{GUG} in $$the gene for hemoglobin. What is the most likely consequence of this mutation?

Accepted Answer

It causes sickle cell anemia by substituting valine for glutamic acid.

Question 3

Which level of protein structure is primarily determined by the sequence of amino acids?

Accepted Answer

Primary structure

Question 4

What type of bond forms between the carboxyl group of one amino acid and the amino group of another during protein synthesis?

Accepted Answer

Peptide bond

Question 5

Which of the following amino acids is most likely to participate in hydrogen bonding due to its side chain?

Accepted Answer

Serine

Question 6

Which statement best explains why the genetic code is described as 'degenerate'?

Accepted Answer

Multiple codons can code for the same amino acid.

Question 7

Which of the following is a function of ribosomes in the cell?

Accepted Answer

They facilitate the translation of mRNA into protein.

Question 8

A mutation changes a codon from $$	ext{UAC} ($$tyrosine) to $$	ext{UAA} ($$stop). What type of mutation is this?

Accepted Answer

Nonsense mutation

Question 9

Which of the following best describes the tertiary structure of a protein?

Accepted Answer

The overall three-dimensional shape stabilized by interactions between R groups.

Question 10

Which of the following is NOT a type of interaction that stabilizes tertiary protein structure?

Accepted Answer

Phosphodiester bonds

Question 11

Which of the following statements about the start codon is correct?

Accepted Answer

The start codon is $$	ext{AUG}$$ and codes for methionine.

Question 12

Which of the following best explains why not all mutations are harmful?

Accepted Answer

Some mutations are silent and do not change the amino acid sequence.

Question 13

Which of the following is a difference between prokaryotic and eukaryotic gene expression?

Accepted Answer

Eukaryotic mRNA is modified by capping and splicing before translation.

Question 14

Which of the following amino acids is most likely to form an ionic bond with aspartate?

Accepted Answer

Lysine

Question 15

Which process describes the removal of introns from pre-mRNA?

Accepted Answer

Splicing

Question 16

Which of the following best describes a frameshift mutation?

Accepted Answer

A mutation caused by insertion or deletion of nucleotides not in multiples of three.

Question 17

Which of the following is a function of tRNA during translation?

Accepted Answer

It brings the correct amino acid to the ribosome based on the mRNA codon.

Question 18

Which of the following is a reason why antibiotics can target bacterial ribosomes without harming human cells?

Accepted Answer

Bacterial ribosomes are structurally different from eukaryotic ribosomes.

Question 19

Which of the following best describes the role of the promoter in transcription?

Accepted Answer

It is the DNA sequence where RNA polymerase binds to initiate transcription.

Question 20

Which of the following is a real-world example of a missense mutation?

Accepted Answer

The substitution of valine for glutamic acid in sickle cell hemoglobin.

Study Guide: Proteins & Gene Expression – Structure, Function, and Mutations

Study Guide - Practice Questions